08 May 2008 19:03:12

LM2596S-12 data

General Description The LM2596 series of regulators are monolithic integrated circuits that provide all the active functions for a step-down (buck) switching regulator, capable of driving a 3A load with excellent line and load regulation. These devices are available in fixed output voltages of 3.3V, 5V, 12V, and an adjustable output version. Requiring a minimum number of external components, these regulators are simple to use and include internal frequency compensation†, and a fixed-frequency oscillator.The LM2596 series operates at a switching frequency of 150 kHz thus allowing smaller sized filter components than what would be needed with lower frequency switching regulators. Available in a standard 5-lead TO-220 package with several different lead bend options, and a 5-lead TO-263 surface mount package. A standard series of inductors are available from several different manufacturers optimized for use with the LM2596 series. This feature greatly simplifies the design of switch-mode power supplies. Other features include a guaranteed ±4% tolerance on output voltage under specified input voltage and output load conditions, and ±15% on the oscillator frequency. External shutdown is included, featuring typically 80 μA standby current. Self protection features include a two stage frequency reducing current limit for the output switch and an over temperature shutdown for complete protection under fault conditions. Features n 3.3V, 5V, 12V, and adjustable output versions n Adjustable version output voltage range, 1.2V to 37V ±4% max over line and load conditions n Available in TO-220 and TO-263 packages n Guaranteed 3A output load current n Input voltage range up to 40V n Requires only 4 external components n Excellent line and load regulation specifications n 150 kHz fixed frequency internal oscillator n TTL shutdown capability n Low power standby mode, IQ typically 80 μA n High efficiency n Uses readily available standard inductors n Thermal shutdown and current limit protection Applications n Simple high-efficiency step-down (buck) regulator n On-card switching regulators n Positive to negative converter Note: †Patent Number 5,382,918. http://www.chinaicmart.com/suppliers/509/LM2596S-12.html

09 May 2008 11:13:02

James Beck

Re: LM2596S-12 data

In article <31005471-4b06-46b8-8e6c-fbcf381a68a5 @w4g2000prd.googlegroups.com >, yangandjiao@126.com says... > > http://www.chinaicmart.com/suppliers/509/LM2596S-12.html > I'll bet they are the real thing too...... We just got hit by some counterfeit adjustable 2596's, over a 5 - 10% drop in efficiency over the real deal and if you could get 2A out of them without having them fry it was a miracle. Filled in National with all the details, but I doubt they will be able to do much. Our distributor got them from a "reputable" reseller in Europe, blah, blah, blah. Naturally, production forged ahead and had about 1K units stuffed before testing started and found the issue.

09 May 2008 12:46:38

JeffM

Bad vendor: chinaicmart.com / dzsc.com -- SPAMs Usenet

>yangandjiao@ 126.com wrote: ::[Product SPAM] >>[SPAM link (redacted by me)] >> In his Google Custom Search Engine for parts, Igor made a point of filtering out these crooks: news:PaqdnRoNAq3-rHXbnZ2dnUVZ_qygnZ2d@giganews.com http://groups.google.com/group/sci.electronics.design/browse_frm/thread/5266f3e66e3279dc/2a2eed93635bb4ec?q=these-are-excluded+Search.without.spammers+dzsc.com James Beck wrote: >I'll bet they are the real thing too...... > A search of the Usenet Archive and/or the Web reveals that this vendor has the business ethics of a sewer rat (in case you couldn't already figure that out). >We just got hit by some counterfeit adjustable 2596's, >over a 5 - 10% drop in efficiency over the real deal[...] > The place all the trade deals (NAFTA, MFN for Red China, etc.) *should* be the most powerful (santioning cheaters) seems to be where they are most toothless.